1. Field of the Invention
The present invention relates to an ultraviolet-sensing sheet, an ultraviolet-sensing set, and an ultraviolet-sensing method.
2. Description of the Related Art
Ultraviolet dose measurement is used in various fields. For example, the ultraviolet dose of an object irradiated with ultraviolet light is measured in a curing reaction of an ultraviolet curable resin or for ultraviolet sterilization of foods or the like. In order to measure an ultraviolet dose, an ultraviolet dosimeter has been used in the related art.
As the ultraviolet dosimeter, a device using photovoltaic power of a semiconductor is generally known. However, this device is expensive and is inconvenient to carry.
In addition, as an inexpensive and convenient ultraviolet dosimeter, a card-shaped ultraviolet dosimeter using a photochromic material is known. However, this ultraviolet dosimeter is reversibly discolored by ultraviolet light. This ultraviolet dosimeter can be used to determine the ultraviolet intensity during irradiation but cannot be used to determine the cumulative dose of ultraviolet light irradiated.
JP1987-112020A (JP-S62-112020A) discloses an element for measurement of an ultraviolet dose in which a composition including a photo activator, a discoloring agent, and an ultraviolet absorber is laminated on a support, the photo activator forming a free radical by ultraviolet irradiation, and the discoloring agent exhibiting a visible color change by the action of the free radical.
JP1997-126887A (H09-126887A) discloses a material for measuring an ultraviolet irradiation dose which is obtained by laminating a resin layer including a radical generator and a colorant on a transparent substrate, the colorant exhibiting a color change by reacting with a radical.